


want some help there...?

by quezq



Category: Undertale (Video Game)
Genre: Fluff, Hurt/Comfort, M/M, Smut, Soul Sex, Subspace, ecto parts, intensely emotional smut, nighty's in it for the nutritional value, so am i honestly
Language: English
Status: Completed
Published: 2020-04-26
Updated: 2020-04-26
Packaged: 2021-03-01 23:29:16
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,007
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23855404
Author URL: https://archiveofourown.org/users/quezq/pseuds/quezq
Summary: this was supposed to be solo killer playing a lighthearted edging game. what the actual fuck happened?i guess nightmare just kicked my door down and demanded control over the fic. i said no, so he wrestled it out of my cold, dead fingers.
Relationships: NightKiller, Nightmare/Killer, Sans/Sans (Undertale)
Comments: 4
Kudos: 92





	want some help there...?

killer's mind goes places, imagining it's nightmare's hand caressing his ribs and teasing his pelvis instead of his own. there's no place for shame over these thoughts, a rare headspace perfect for just pleasure; he deserves to feel good things and right know he's sure of that, even if he will go straight back to doubting when he's done.

his blush deepens and breathing grows laborious as he repeatedly hits sensitive spots inside himself with a delighted smile. killer knows himself better than anyone else, and his own hand knows exactly how to produce those gasps of almost surprise at how _good_ it feels, working by itself in excited, determined pursue of self-love. he bites back a moan, having learned to remain silent between the thin walls of the shared house.

light suddenly breaks in as the door opens and nightmare stops just short of stepping in, eyelight immediately shrinking when he looks at killer. he doesn't see anything, as all of his naked body is concealed by a soft blanket, but there's no way he doesn't realize what the other is doing, and killer knows that he knows. all the self-consciousness he had been keeping at bay floods in at once, the glow that had been of arousal changing slightly in hue to one of shame as the voices in his head rush back to remind him how worthless and disgusting he really is. he was _so_ close, too - and the deep loneliness and embarrassment that hit in the middle of this already jarring whiplash have him fighting back tears.

he had hoped his boss would ignore the plethora of emotions he definitely noticed permeating the air so they could both pretend this never happened, but instead the skeleton wordlessly comes in, closes the door behind himself and sits down on killer's bed.

he panics. no matter how well he may think he knows nightmare, the other insists on being too unpredictable at all times.

said unpredictability gets confirmed by the hand that cups the back of his skull, petting gently. killer leans into it, eyesockets narrowing; he was always a sucker for affection of any kind, especially when it came from the very source of these stupid _feelings_ he couldn't shake since day one. he gets so lost in the soothing contact it takes a while to realize the _other_ hand slowly crawling into his personal space under the blanket, caressing down his sternum then reaching inside his ribcage, not without several unnecessary slimy grazes.

"wait, what are you-" the sentence is cut by an exclamation of newfound vulnerability as his soul materializes in nightmare's grasp and gets pulled outside of his body.

killer watches the other closely examine the red, jello-consistency heart, trying not to make sinful noises spurred by fingers kneading it and sending ripples of a foreign pleasure through his marrow. containment fails miserably when nightmare brings the soul to his mouth and slowly licks a stripe down the middle, savoring something only he can perceive. all shame, fear and stress get ripped away from killer at once, which throws him into unprecedented bliss only achievable by sucking the negativity straight from the source, not giving it a single second to fester and spread. that's his confirmation this can't be a dream; his mind couldn't possibly do this on its own.

he clamps a hand over his mouth to stop an incoming stream of curses, but whimpers continue to escape as the warm tongue so intimately swirls around his very being. he can barely think, but when he manages l, his thoughts are flooded with the realization of _who's_ doing this, to _him,_ which makes the squirming increase tenfold. stars, it's so unfair and he's so pathetically helpless, his figurative brain screams, but all the edge in those thoughts gets skillfully, deliciously extracted by his boss - no, his _master_ , he rethinks without a shadow of a doubt - before he can get even a scrape from them.

over several minutes of disabling pleasure, killer sometimes looks up with hazy, slitted eyesockets. it makes nightmare smirk back, adding pressure and pattern and even a few nibbles to his ministrations, daring the writhing skeleton not to tear his eyelights away from the deeply flustering sight. he repeatedly fails the unspoken challenge, bundling up the blanket to hide his blazing hot face behind, but today all the punishments are rewards.

nightmare takes the whole determination-riddled monster soul in his mouth, ecto never ceasing its gentle movement, which leaves his hands free to explore killer's slick hole, just ready enough for four fingers to hilt inside without any resistance from its owner. when they curl, at the same time that three slimy fingers from the other hand pick up a pace of back-and-forth on his throbbing clit, he starts to build fast. restraint but a memory, killer begs for release when his lord dials everything back for a bit, but it is promptly granted. his pussy comes first, and it's so warm, spine arching with the delightful waves radiating from the epicenter. only two beats later, the dripping overstimulated soul sends him into a second, stronger, whole-body orgasm, and the intersection has him half-moaning, half-wailing from the otherworldly sensations, spasming while curled up and clenching his fists around the blanket's fabric.

he comes down from it after some long seconds of eternity, being gradually and kindly lowered into afterglow. the hand withdraws from his dissipating magic and the soul is pushed back in his body, where its physical shape disappears; however, the creeping negativity never arrives, replaced in its entirety with tears of fulfillment and exhaustion. nightmare scritches his head, like the little kitten he's been reduced to, and he purrs accordingly, with no strength or will left to put up any act of nonchalance. killer had offered himself before, but never had he been so thoroughly _claimed._

the overwhelm of gratitude and positive submissiveness probably brings no satisfaction, and granted, it doesn't take very long, but his lord does not leave - not until he is asleep.

**Author's Note:**

> this was supposed to be solo killer playing a lighthearted edging game. what the actual fuck happened?  
> i guess nightmare just kicked my door down and demanded control over the fic. i said no, so he wrestled it out of my cold, dead fingers.


End file.
